• Journal of Microbiology and Biotechnology
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• v.1 no.2
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• pp.85-89
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• 1991

The aim of this study is to elucidate characteristics of ${\beta}-lactamase$ inhibitor produced by Streptomyces sp. SMF-19 isolated from soil was found to produce proteinaceous extracellular ${\beta}-lactamase$ inhibitor. The ${\beta}-lactamase$ inhibitor was purified through ammonium sulfate fractionation, gel filtration, anion exchange chromatography and fast performace liquid chromatography. The molecular weight of the ${\beta}-lactamase$ inhibitor was estimated to be about 48,000 by SDS-PAGE. The mode of inhibition against penicillin G as a substrate was uncompetitive. The ${\beta}-lactamase$ inhibitor was stable in wide pH range but unstable at high temperature above $50^{\circ}C$.

• Journal of Microbiology
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• v.34 no.2
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• pp.184-191
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• 1996

The cellular fatty acids and quinones of streptomycetes isolated from volcanic soils were analysed. The strains contained fatty acids of 14 to 17 carbon chains, and 12-methyltetradecanoic acid and 14 methylpentadecanoic acid were dominant in most strains. The total profiles consisted of 74% branched fatty acid family, 16.8% linear family and 8.2% unsaturated family. The largest cluster of grey spore meases defined by numerical classification was separated from the remainders in the principal component analysis, but the other clusters were overlapped with one another. In the analysis of respiratory quinones, all of the strains contained either the menaquinone of 9 isoprene units with 6 hydrogenations of 8 hydrogenations as the major species. The distribution of menaquinones among the clusters could provide an important key in the chemotaxonomy of streptomycetes.

• Journal of Microbiology and Biotechnology
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• v.3 no.3
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• pp.174-180
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• 1993

A strain SMF14 producing an extracellular $\beta$-lactamase was isolated from soil and identified to be a strain of Streptomyces aureofaciens. $\beta$-Lactamase was purified from the cell free culture broth through batchwise hydroxyapatite adsorption, anion exchange chromatography on DEAE Sephadex A-50, gel filtration on Sephadex G-75, and adsorption chromatography on hydroxyapatite. The molecular mass was estimated to be about 43 kDa by SDS-PAGE. The $\beta$-lactamase had substrate specificity to penicillins and it was inhibited by clavulanic acid, being classified to the group 2a of penicillinase.. The optimal reaction pH and temperature were pH 6.0~7.5 and $50^{\circ}C$. The $K_m, and V_{max}$ values of $\beta$-lactamase for penicillin G were calculated to be 1.72 mM and 5.4$\times$$10^5 \mu M \cdot min^{-1}$, respectively.

• Journal of Plant Biotechnology
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• v.49 no.2
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• pp.107-117
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• 2022

Increasing soil salinity is one of the global challenges that the agriculture sector in Egypt has been facing; 33% of the cultivated land in Egypt, which includes merely 3% of the entire land area, is already salinized. The present review sheds light on the role of fungal biopriming, a technique in which hydrated seeds are inoculated with beneficial fungal flora, in mitigating the deleterious influence of NaCl tension. Endophytic fungi were recognized to be able to interact with several plant species, markedly contributing to the mitigation of NaCl stress in these plants, such that some plants get impoverished to their absent associated microbes under stressful conditions.

• Microbiology and Biotechnology Letters
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• v.35 no.2
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• pp.150-157
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• 2007

The advanced bioremediation of diesel-contaminated soil through the exploration of bacterial interaction with plants was studied. A diesel-degrading rhizobacterium, Rhodococcus sp.412, and a plant species, Zea mays, having tolerant against diesel was selected. Zea mays was seeded in uncontaminated soil or diesel-contaminated soil with or without Rhodococcus sp. 412. After cultivating for 30 days, the growth of Zea mays in the contaminated soil inoculated with Rhodococcus sp. 412 was better than that in the contaminated soil without the bacterium. The residual diesel concentrations were lowered by seeding Zea mays or inoculating Rhodococctis sp. 412. These results Indicate that the simultaneous use of Zea mays and Rhodococcus sp. 412 can give beneficial effect to the remediation of oil-contaminated soil. Bacterial community was characterized using a 16S rDNA PCR and denaturing gradient gel electrophoresis (DGGE) fingerprinting method. The similarities of DGGE fingerprints were $20.8{\sim}39.9%$ between the uncontaminated soil and diesel contaminated soil. The similarities of DGGE fingerprints were $21.9%{\sim}53.6%$ between the uncontaminated soil samples, and $31.6%{\sim}50.0%$ between the diesel-contaminated soil samples. This results indicated that the structure of bacterial community was significantly influence by diesel contamination.

• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.408-412
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• 2003

The purpose of this study was to evaluate the Influence of oil concentration and inoculum size on petroleum biodegradation in soil by Nocardia sp. H17-1, isolated from oil-contaminated soil. To investigate the effect of initial oil concentration on total petroleum hydrocarbon (TPH) degradation, the soil was artificially contaminated with 10, 50 or 100 g of Arabian light oil per kg of soil, respectively. After 50 days, Nocardia sp. H17-1 degraded 78,94 and 53% of the each initial TPH concentration, respectively. Also, it produced 1.35, 4.21, and 5.91 mmol of $CO_2$ per g of soil, respectively. The degradation rate constant (k) of TPH was decreased in proportion to the initial oil concentrations while $CO_2$ production was increased with the concentration. The growth of Nocardia sp. H17-1 was remarkably inhibited when it was inoculated into soil containing 100 g of oil per kg of soil. To evaluate the effect of the inoculum size, the soil was artificially contaminated with 50 g of Arabian light oil per kg of soil, and inoculated with $3${\times}$10^{6}$ , $5${\times}$10^{7}$ , $2${\times}$10^{8}$ cells per g of soil, respectively. After 50 days, the degradation of TPH was remained with similar in all treatment but degradation rate constant (k) and evolved $CO_2$ was increased with increasing the inoculum size.

• Microbiology and Biotechnology Letters
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• v.24 no.3
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• pp.311-315
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• 1996

A cytotoxic material was produced by strain No. 5-99 which was isolated from soil. Analyzing the cell wall components, LL-diaminopimelic acid was identified. From the existance of glycine in the cell wall, this strain was identified to Streptomyces sp. which has cell wall chemotype I and peptidoglycan type A3 connected by glycine. So, we named this strain to Streptomyces sp. YJB-599. The Active material was purified through solvent extraction, silica gel column chromatography and crystallized to needle-shaped white -crystal. Analyzing the structure of this crytal by instrumental analysis and database, it was determined to genistein.

• Journal of Microbiology and Biotechnology
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• v.3 no.1
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• pp.57-60
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• 1993

The herbicidal compound, 3D5 was isolated from the culture broth of strain 3D5, a soil isolate. Based on taxonomic studies, this culture was identified as Streptomyces sp. 3D5.

• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.707-710
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• 1992

Bacillus stearothermophilus No.239 isolated from soil was mutated with N-methyl-N'nitro-N-nitrosoguanidine (MNNG) to yield a series of mutants with increasing levels of cyclomalto-dextrin glucanotransferase (EC 2.4.1.19` CGTase) production. After five consecutive mautation steps, a mutant MNNG 8 with about 14 times of CGTase activity than the parent strain was obtained.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.209.4-209
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• 1978

Previously, we reported the inhibitory substane which reacts on venoms proteinases and haemorrha-ghagic factors. The active substsnce was originated from soil fungi. This report describes the results of molecular weight determination, the activity by the derivatives, and also the reaction in vivo by the administration of sample L175-68-B.